Noise Margin expectations?

[#1]

As DMT doesn't want to work can you post the bits per tone graph from routerstats

[#2]

Graph is attached.
Jim

[#3]

Compared to mine - you have more of the higher frequency tones - to be expected with a lower attenuation - but a lot of worrying gaps.
I am a bit out of my depth here but the more expert members on the forums may be able to offer more guidance.

[#4]

Thank you for your help so far.

[#5]

i am sure antherone will be geting hungry  and need is fix of line stats soon
my 50.5 db line on adsl2 bitloading below

[#6]

OK, so that we can try and look at this with as much background as possible, do you know how long it's been like this (roughly), do you know if it's been better?
Do you (know if you) live near any major radio transmitters? (I'll send you a PM).

[#7]

Hi
No major radio transmitters nearer than 10-15 miles - television transmitters are all huge distances - no mobile phone antenna nearby either that I know of. No industrial plants
Its very hard to say when it started. I have been on a 1Meg line for  circa 5 years without trouble but changed to max and to Pipex maybe 12 months ago and was pleased to get something faster than 1Meg. It was never going to be lightening as I am maybe 2 miles from the exchange.
Took some interest in speed about 3 months ago and installed a NT5 filtered front and reorganised my wiring a bit. The modem is within inches of the master socket but then has an ethernet cable going off to a wireless modem in the loft.. In normal operation there is a dect set and a standard phone plugged into the phone side of the filter and an extension wire going away around the house to various phone points - mostly originally put there for a modem to go next to the computer but now unused. Was pleased to get 3600kbits or thereabouts at that time. As said above, the evidence is that disconnecting all internal wiring makes no difference. I think the noise level was about a steady 10db at that time because I could not understand why it was so high. However, not solid evidence.
Maybe 3 weeks ago, everything stopped - broadband, phone, the lot. Eventually BT turned up and decided that they had accidentally disconnected us at the exchange. Got that sorted, no idea about the noise at that time but I am fairly sure the speed was still about 3600. So I then waited for my profile (caution - uneducated use of technical term) to go up.
Lately the net seems to have been very slow. Some pages just seemed to take forever to get started - but if I re-trigger them, they come in quick. However, I mostly use a Linux based laptop over the wireless connection and am always mucking round with it, so I am never too sure whether that is me or the net.
Anyway, the other day, I read the forum and some of the posts about speed. Loaded up Routerstat and found that my speed had dropped to something like 2900 and the noise margin was at a high of 3 bouncing down to 2 or 1 and to 0 occasionally. Mild panic, then had various other panics so left it. Eventually got back to it and found that it was now peaking at 10db with lots of drops to 7, 6 maybe 5. No reason I know of for the improvement.
Then as it was a Sunday and as I had some time, I disconnected the phones and did some tests and that brings us back in at the top of this thead.
Jim

[#8]

Its now 10pm. Routerstat shows mostly 7db with odd peaks upwards to 8 or even 9 but mostly downward peaks to 5, 4 or very occasionally 3.
Since I restarted the modem this morning, the bitswaps graph shows every tone has changed several times and some are going off the graph at the top.
So far the downstream synch speed is holding firm at 3700.
Jim

[#9]

Can you post that latest graph Jim, it may help.

[#10]

Sorry, I haven't got a copy of that one stored but I will aim to store one this evening and load that one up.
Jim

[#11]

Tonights graph attached.  The break is where the PC went into hibernation briefly
I am having a struggle to keep the telnet graphs recording - they work for a while then seem to stop unless I restart Routerstats or set the modem into debug mode manually. Any thoughts on what I am doing wrong there. (Ignore this if it just confuses the thread)
Jim

[#12]

I'll see if OJ has any thoughts on the graph recording. I'm still checking out the possible MW transmitter issues.
Keep listening to that phone line - all you should hear is a very quiet, barely discernable shhhh type sound. Any crackling  or other intermittent noises indicates a possible connection problem somewhere.

[#13]

I always set debug mode manually if I need to reboot the router or there is a power cut (like the plug pulled out) otherwise telnet doesn't work properly. I am using an older version of routerstats though

[#14]

@OJ
But having got it set into debug mode and readings being taken, does yours not stop taking telnet recordings after a while.
I get the impression that my router decides that for security reasons (or computer stupidity) it terminates debug mode after some time (lets say 15 minutes, I have not timed it). It will not supply fresh data unless either I, or routerstats resends the debug mode command - and routerstats does not send it so I have to.
As soon as I send the command (from my browser), routerstats starts getting more data for a while at least.
I'll try to take a bit more notice of the times, that might be a clue. What I was wondering was whether I had missed some setting like "keep sending debug" but I guess not or you would have suggested it.
Jim

[#15]

I haven't seen the problem but a bit of digging threw up this screen in routerstats my log is set for every 5 minutes so that is probably the reason.
I will keep digging to find out how to alter it as it is greyed out at present